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https://www.askthetrades.co.uk/cgi-bin/yabb/YaBB.pl DIY Forum >> Plumbing Questions >> Baxi 105E boiler - Stuck in DHW mode https://www.askthetrades.co.uk/cgi-bin/yabb/YaBB.pl?num=1175257966 Message started by Banjo on Mar 30^th, 2007, 1:32pm

Title: Baxi 105E boiler - Stuck in DHW mode
Post by Banjo on Mar 30^th, 2007, 1:32pm

On my Baxi 105E instant combi boiler the pushrod in the DHW differential stays out after the tap is turned off and hence the system stays in DHW mode.

I've cleaned and shined and greased the pushrod and cleaned out the inside of the diffential including the rod on the thrust plate. I've checked the diaphram - looks OK. I've checked that the sensing pipes are clear and I've cleaned both DHW filters. But no joy :(

I've checked the microswitch operation and its fine so it's down to the diff or whatever drives it.

What should I try next. :-?

Title: Re: Baxi 105E boiler - Stuck in DHW mode
Post by Banjo on Mar 31^st, 2007, 10:40am

a little more info:-

Before the central heating kicks in, the DHW diff pushrod behaves OK i.e it goes back in when I turn off the hot tap.
When the CH has been on for a short time the pushrod stays out for a a few seconds after the tap is turned off.
When the CH has been on for an hour or so, as soon as I use the hot tap the pushrod stays out for good - I can only then get out of DHW mode by detaching the microswitch from the DHW pushrod.

Something to do with the temperature of the manifold maybe??????